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2. Exciting H2 Molecules for Graphene Functionalization

Author

Kyhl, Line, Bisson, Régis, Balog, Richard, Groves, Michael N, Kolsbjerg, Esben Leonhard, Cassidy, Andrew Martin, Jørgensen, Jakob Holm, Halkjær, Susanne, Miwa, Jill A, Čabo, Antonija Grubišić, Angot, Thierry, Hofmann, Philip, Arman, Mohammad Alif, Urpelainen, Samuli, Lacovig, Paolo, Bignardi, Luca, Bluhm, Hendrik, Knudsen, Jan, Hammer, Bjørk, and Hornekaer, Liv

Subjects
Chemical Sciences, Physical Chemistry, Physical Sciences, Atomic, Molecular and Optical Physics, Condensed Matter Physics, Affordable and Clean Energy, graphene, vibrational excitation, nanostructured functionalization, band gap engineering molecular hydrogen, catalysis, band gap engineering, molecular hydrogen, Nanoscience & Nanotechnology
Abstract

Hydrogen functionalization of graphene by exposure to vibrationally excited H2 molecules is investigated by combined scanning tunneling microscopy, high-resolution electron energy loss spectroscopy, X-ray photoelectron spectroscopy measurements, and density functional theory calculations. The measurements reveal that vibrationally excited H2 molecules dissociatively adsorb on graphene on Ir(111) resulting in nanopatterned hydrogen functionalization structures. Calculations demonstrate that the presence of the Ir surface below the graphene lowers the H2 dissociative adsorption barrier and allows for the adsorption reaction at energies well below the dissociation threshold of the H-H bond. The first reacting H2 molecule must contain considerable vibrational energy to overcome the dissociative adsorption barrier. However, this initial adsorption further activates the surface resulting in reduced barriers for dissociative adsorption of subsequent H2 molecules. This enables functionalization by H2 molecules with lower vibrational energy, yielding an avalanche effect for the hydrogenation reaction. These results provide an example of a catalytically active graphene-coated surface and additionally set the stage for a re-interpretation of previous experimental work involving elevated H2 background gas pressures in the presence of hot filaments.

Published
2018

3. Initial study on thermal stability of cold spray tantalum coating irradiated with deuterium for fusion applications

Author

Ialovega, Mykola, primary, Dabney, Tyler, additional, Navarro Gonzalez, Marcos, additional, Yeom, Hwasung, additional, Velez, Danah, additional, Willing, Evan, additional, Anderson, Jay K, additional, Angot, Thierry, additional, Bisson, Régis, additional, Forest, Cary, additional, Kreter, Arkadi, additional, Schmitz, Oliver, additional, and Sridharan, Kumar, additional

Published
2023
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5. Helium-induced morphology evolution in tungsten under thermal treatment

Author

Ialovega, Mykola, primary, Bernard, Elodie, additional, Barthe, Marie-France, additional, Bisson, Régis, additional, Campos, Andrea, additional, Cabié, Martiane, additional, Neisius, Thomas, additional, Sakamoto, Ryuichi, additional, Kreter, Arkadi, additional, Grisolia, Christian, additional, Angot, Thierry, additional, and Martin, Celine, additional

Published
2022
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6. Optical Properties of Tungsten: A Parametric Study to Characterize the Role of Roughness, Surface Composition and Temperature

Author

Pappalardo, Federica, primary, Romero Lairado, Francisco Romero, additional, Louis de Canonville, Cyprien Louis de, additional, Martin, Céline, additional, Giacometti, Gregory, additional, Serin, Guillaume, additional, Salomon, Eric, additional, Angot, Thierry, additional, Gallais, Laurent, additional, Bisson, Régis, additional, and Minissale, Marco, additional

Published
2022
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8. L'Interface Plasma-Paroi

Author

Bufferand, Hugo, Bisson, Régis, Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Bisson, Régis

Subjects
[PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], [PHYS.PHYS.PHYS-PLASM-PH] Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], [PHYS.COND.CM-MS] Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [PHYS.PHYS.PHYS-CHEM-PH] Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]
Abstract

International audience; Dans l'histoire de la recherche sur la fusion par confinement magnétique, l'interface entre le plasma et la paroi n'a pas toujours été sur le devant de la scène. Près de 70 ans après les premiers tokamaks, contrôler le plasma de bord et son interaction avec la paroi est devenu un enjeu majeur et une thématique de premier plan dans la recherche en fusion.

Published
2020

9. Physique des flux de matière

Author

Pégourié, Bernard, Bisson, Régis, Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Bisson, Régis

Subjects
[PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], [PHYS.PHYS.PHYS-PLASM-PH] Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], [PHYS.COND.CM-MS] Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [PHYS.PHYS.PHYS-CHEM-PH] Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]
Abstract

International audience; Dans un réacteur de fusion deutérium-tritium par confinement magnétique, la première paroi devra assurer simultanément la régénération du tritium et le contrôle des flux de chaleur et particules à la périphérie du plasma. La grande inhomogénéité des flux sur la paroi et la forte sensibilité des performances du coeur à la présence de particules érodées représentent un vrai défi pour les réacteurs futurs. Celui-ci ne pourra être relevé que par un effort conjoint de simulation intégrant la paroi de façon explicite et de travaux de laboratoire pour comprendre en détail les phénomènes élémentaires régissant les interactions plasma-matériaux.

Published
2020

10. Optical properties of metals submitted to tokamak conditions

Author

Louis De Canonville, cyprien, Minissale, Marco, Pardanaud, C, Bisson, Régis, Gallais, Laurent, Institut FRESNEL (FRESNEL), Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU), Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), and Gallais, Laurent

Subjects
[PHYS.PHYS.PHYS-OPTICS] Physics [physics]/Physics [physics]/Optics [physics.optics], [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2021

12. The effect of surface temperature on optical properties of molybdenum mirrors in the visible and near-infrared domains

Author

Minissale, Marco, Zeweldi, G.T., Bisson, Régis, Gallais, Laurent, Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), ILM (ILM), Institut FRESNEL (FRESNEL), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), ANR-11-IDEX-0001,Amidex,INITIATIVE D'EXCELLENCE AIX MARSEILLE UNIVERSITE(2011), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), and Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)

Subjects
Molybdenum, Total emissivity, ITER, Temperature, Lorentz-Drude model, Refractive index, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Reflectivity, First Mirrors
Abstract

International audience; Molybdenum mirrors will be used in several optical diagnostics to control the plasma in the ITER tokamak. In this harsh environment, mirrors can undergo transient temperature rises. Thus the knowledge of the temperature dependence of optical properties of molybdenum is necessary for a good operation of optical systems in ITER. Molybdenum optical properties have been extensively studied at room temperature, but little has been done at high temperatures in the visible and near-infrared domains. We investigate here the temperature dependence of molybdenum reflectivity from the ambient to high temperatures (

Published
2018

13. Laser remote heating in vacuum environment to study temperature dependence of optical constants and phase change for metallic and dielectric films

Author

Minissale, M., Zeweldi, G.T., Moisset, Charles, iliopoulos, konstantinos, Bisson, Régis, Gallais, Laurent, Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Institut FRESNEL (FRESNEL), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), and Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)

Subjects
[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], ComputingMilieux_MISCELLANEOUS
Abstract

National audience

Published
2018

14. Peculiar release kinetics of deuterium from polycrystalline tungsten revealed by a laser induced desorption technique: experiment and modeling

Author

Minissale, Marco, Hodille, E, Ghiorghiu, F, Markelj, S., Martin, Céline, Ferro, Y, Barthe, M.F., Becquart, C, Mougenot, Jonathan, ANGOT, Thierry, Grisolia, C, Gallais, Laurent, Bisson, Régis, Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), ILM (ILM), Institut FRESNEL (FRESNEL), Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU), Jozef Stefan Institute [Ljubljana] (IJS), Conditions Extrêmes et Matériaux : Haute Température et Irradiation (CEMHTI), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université d'Orléans (UO), Unité Matériaux et Transformations - UMR 8207 (UMET), Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), Laboratoire des Sciences des Procédés et des Matériaux (LSPM), Université Paris 13 (UP13)-Institut Galilée-Université Sorbonne Paris Cité (USPC)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Université d'Orléans (UO)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), and Centre National de la Recherche Scientifique (CNRS)-Université Sorbonne Paris Cité (USPC)-Institut Galilée-Université Paris 13 (UP13)

Subjects
[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2018

15. Laser Induced Desorption: a new technique to evaluate and control fusion fuel content of tungsten tiles of tokamaks

Author

Minissale, M., Angot, Thierry, Faure, J.B., Grisolia, C, Gallais, Laurent, Bisson, Régis, Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), ILM (ILM), Institut FRESNEL (FRESNEL), Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), and Gallais, Laurent

Subjects
[PHYS.PHYS.PHYS-OPTICS] Physics [physics]/Physics [physics]/Optics [physics.optics], [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2018

17. Alignment dependent chemisorption of vibrationally excited CH4(ν3) on Ni(100), Ni(110), and Ni(111).

Author

Yoder, Bruce L., Bisson, Régis, Morten Hundt, P., and Beck, Rainer D.

Subjects
*CHEMISORPTION, *METHANE, *INFRARED technology, *CHEMICAL reactions, *QUANTUM theory, *MOLECULAR dynamics, *ANGULAR momentum (Mechanics)
Abstract

We present a stereodynamics study of the dissociative chemisorption of vibrationally excited methane on the (100), (110), and (111) planes of a nickel single crystal surface. Using linearly polarized infrared excitation of the antisymmetric C-H stretch normal mode vibration (ν3), we aligned the angular momentum and C-H stretch amplitude of CH4(ν3) in the laboratory frame and measured the alignment dependence of state-resolved reactivity of CH4 for the ν3 = 1, J = 0-3 quantum states over a range of incident translational energies. For all three surfaces studied, in-plane alignment of the C-H stretch results in the highest dissociation probability and alignment along the surface normal in the lowest reactivity. The largest alignment contrast between the maximum and minimum reactivity is observed for Ni(110), which has its surface atoms arranged in close-packed rows separated by one layer deep troughs. For Ni(110), we also probed for alignment effects relative to the direction of the Ni rows. In-plane C-H stretch alignment perpendicular to the surface rows results in higher reactivity than parallel to the surface rows. The alignment effects on Ni(110) and Ni(100) are independent of incident translational energy between 10 and 50 kJ/mol. Quantum state-resolved reaction probabilities are reported for CH4(ν3) on Ni(110) for translational energies between 10 and 50 kJ/mol. [ABSTRACT FROM AUTHOR]

Published
2011
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18. State-resolved reactivity of CH4 on Pt(110)-(1×2): The role of surface orientation and impact site.

Author

Bisson, Régis, Sacchi, Marco, and Beck, Rainer D.

Subjects
*METHANE, *MOLECULAR dynamics, *VIBRATION (Mechanics), *MANURE gases, *SCISSION (Chemistry)
Abstract

The reactivity of methane (CH4) on Pt(110)-(1×2) has been studied by quantum state-resolved surface reactivity measurements. Ground state reaction probabilities, S0(v=0)≅S0(laser-off), as well as state-resolved reaction probabilities S0(2ν3), for CH4 excited to the first overtone of the antisymmetric C–H stretch (2ν3) have been measured at incident translational energies in the range of 4–64 kJ/mol. We observe S0(2ν3) to be up to three orders of magnitude higher than S0(v=0), demonstrating significant vibrational activation of CH4 dissociation on Pt(110)-(1×2) by 2ν3 excitation. Furthermore, we explored the azimuthal and polar incident angle dependence of S0(2ν3) and S0(v=0) for a fixed incident translational energy Et=32 kJ/mol. For incidence perpendicular to the missing row direction on Pt(110)-(1×2) and polar angles θ>40°, shadowing effects prevent the incident CH4 molecules from impinging into the trough sites. Comparison of this polar angle dependence with reactivity data for incidence parallel to the missing rows yields state-resolved site specific reactivity information consistent with a Pt(110)-(1×2) reactivity that is dominated by top layer Pt atoms located at the ridge sites. A comparison of S0(v=0) measured on Pt(110)-(1×2) and Pt(111) yields a lower average barrier for Pt(110)-(1×2) by 13.7±2.0 kJ/mol. [ABSTRACT FROM AUTHOR]

Published
2010
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19. Exciting H2 Molecules for Graphene Functionalization

Author

Kyhl, Line, primary, Bisson, Régis, additional, Balog, Richard, additional, Groves, Michael N., additional, Kolsbjerg, Esben Leonhard, additional, Cassidy, Andrew Martin, additional, Jørgensen, Jakob Holm, additional, Halkjær, Susanne, additional, Miwa, Jill A., additional, Grubišić Čabo, Antonija, additional, Angot, Thierry, additional, Hofmann, Philip, additional, Arman, Mohammad Alif, additional, Urpelainen, Samuli, additional, Lacovig, Paolo, additional, Bignardi, Luca, additional, Bluhm, Hendrik, additional, Knudsen, Jan, additional, Hammer, Bjørk, additional, and Hornekaer, Liv, additional

Published
2017
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21. Vibrational activation in direct and precursor-mediated chemisorption of SiH4 on Si(100).

Author

Bisson, Régis, Dang, Tung T., Sacchi, Marco, and Beck, Rainer D.

Subjects
*CHEMISORPTION, *QUANTUM chemistry, *REACTION mechanisms (Chemistry), *SEMICONDUCTORS, *SILANE compounds, *SILICON, *POLYATOMIC molecules
Abstract

The quantum state-resolved reactivity S0 of SiH4 on Si(100)-2×1 has been measured for the first time for two vibrationally excited Si–H stretch local mode states (|2000> and |1100>) as well the ground state S0 as a function of translational energy En and surface temperature Ts. We observe evidence for both direct and precursor-mediated chemisorption pathways. As expected, increasing En (or Ts) decreases S0 for the precursor-mediated reaction and increases S0 for the direct chemisorption. However, vibrational excitation of the incident SiH4 increases S0 for both the direct and the precursor-mediated pathway with a higher S0 for the |2000> state than for the |1100> state, indicating a nonstatistical reaction mechanism. [ABSTRACT FROM AUTHOR]

Published
2008
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22. Understanding the retention of hydrogen isotopes and controlling their release: an integrated approach applied to tungsten materials

Author

Bisson, Régis, Hodille, E.A., Ghiorghiu, F, Minissale, Marco, Haddab, Yassine, Zaloznik, A, Fernandez, N, Martin, C, Angot, Thierry, Barthe, Marie-France, Markelj, S, Gallais, Laurent, Ferro, Yves, Becquart, Charlotte, Mougenot, J, Grisolia, Christian, Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), ILM (ILM), Institut FRESNEL (FRESNEL), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Jozef Stefan Institute [Ljubljana] (IJS), Conditions Extrêmes et Matériaux : Haute Température et Irradiation (CEMHTI), Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Unité Matériaux et Transformations - UMR 8207 (UMET), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), Laboratoire des Sciences des Procédés et des Matériaux (LSPM), Centre National de la Recherche Scientifique (CNRS)-Université Sorbonne Paris Cité (USPC)-Institut Galilée-Université Paris 13 (UP13), Université d'Orléans (UO)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Université Paris 13 (UP13)-Institut Galilée-Université Sorbonne Paris Cité (USPC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU), and Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)

Subjects
[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2016

23. Releasing of hydrogen isotopes trapped in tungsten samples through laser remote heating under Ultra High Vacuum environment

Author

Minissale, Marco, Ghiorghiu, F, Angot, Thierry, Grisolia, Christian, Gallais, Laurent, Bisson, Régis, Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), ILM (ILM), Institut FRESNEL (FRESNEL), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), and Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)

Subjects
[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2016

24. Retention and release of hydrogen isotopes in tungsten plasma facing components: understanding and controlling with an integrated approach

Author

Bisson, Régis, Hodille, E.A., Ghiorghiu, F, Minissale, Marco, Addab, Y., Založnik, A, Martin, Céline, ANGOT, Thierry, Barthe, Marie-France, markelj, s, Gallais, Laurent, Becquart, Charlotte, mougenot, j, Grisolia, Christian, Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), ILM (ILM), Institut FRESNEL (FRESNEL), Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU), Jozef Stefan Institute [Ljubljana] (IJS), Conditions Extrêmes et Matériaux : Haute Température et Irradiation (CEMHTI), Université d'Orléans (UO)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Unité Matériaux et Transformations - UMR 8207 (UMET), Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), Laboratoire des Sciences des Procédés et des Matériaux (LSPM), Université Paris 13 (UP13)-Institut Galilée-Université Sorbonne Paris Cité (USPC)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), and Centre National de la Recherche Scientifique (CNRS)-Université Sorbonne Paris Cité (USPC)-Institut Galilée-Université Paris 13 (UP13)

Subjects
[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2016

25. Tungsten and Hydrogen isotopes Interactions: an integrated approach

Author

Bisson, Régis, Barthe, Marie-France, Markelj, S, Gallais, Laurent, Cartry, Gilles, Martin, Céline, Ferro, Yves, Angot, Thierry, Becquart, Charlotte, Mougenot, J, Grisolia, Christian, Plasma-Surface, Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Conditions Extrêmes et Matériaux : Haute Température et Irradiation (CEMHTI), Université d'Orléans (UO)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Jozef Stefan Institute [Ljubljana] (IJS), ILM (ILM), Institut FRESNEL (FRESNEL), Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU), Unité Matériaux et Transformations - UMR 8207 (UMET), Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), Laboratoire des Sciences des Procédés et des Matériaux (LSPM), Université Paris 13 (UP13)-Institut Galilée-Université Sorbonne Paris Cité (USPC)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), and Centre National de la Recherche Scientifique (CNRS)-Université Sorbonne Paris Cité (USPC)-Institut Galilée-Université Paris 13 (UP13)

Subjects
[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2015

26. Deuterium adsorption on (and desorption from) SiC(0001)-(3×3), (√3×√3)R30°, (6√3×6√3)R30° and quasi-free standing graphene obtained by hydrogen intercalation

Author

Bocquet, François C., Bisson, Régis, Themlin, Jean-Marc, Layet, J.-M., Angot, Thierry, Institut des Matériaux, de Microélectronique et des Nanosciences de Provence (IM2NP), Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), and Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat]
Abstract

International audience; We present a comparative high-resolution electron energy-loss spectroscopy study on the interaction of atomic hydrogen and deuterium with various reconstructions of SiC(0 0 0 1). We first show that on both the (3 × 3) and reconstructions, deuterium atoms only bind to silicon atoms, thereby confirming the silicon-rich appellation of these reconstructions. Deuterium passivation of the (3 × 3) is only reversible when exposed to atomic deuterium at a surface temperature of 700 K since tri- and dideuterides, necessary precursors for silicon etching, are not stable. On the other hand, we show that the deuteration of the is always reversible because precursors to silicon etching are scarce on the surface. Then, we demonstrate that hydrogen (deuterium) adsorption at 300 K on both the (buffer-layer) and the quasi-free-standing graphene occurs on carbon atoms justifying their carbon-rich appellation. Comparison of the deuterium binding in the intercalation layer of quasi-free-standing graphene with the deuterated surface provides some indication on the bonding structure at the substrate intercalation layer. Finally, by measuring C-H (C-D) vibrational frequencies and hydrogen (deuterium) desorption temperatures we suggest that partial sp2-to-sp3 rehybridization occurs for the carbon atoms of the buffer-layer because of the corrugation related to covalent bonding to the SiC substrate. In contrast, on quasi-free-standing graphene hydrogen (deuterium) atoms adsorb similarly to what is observed on graphite, i.e. without preferential sticking related to the underlying SiC substrate.

Published
2014

29. Exciting H2Molecules for Graphene Functionalization

Author

Kyhl, Line, Bisson, Régis, Balog, Richard, Groves, Michael N., Kolsbjerg, Esben Leonhard, Cassidy, Andrew Martin, Jørgensen, Jakob Holm, Halkjær, Susanne, Miwa, Jill A., Grubišić Čabo, Antonija, Angot, Thierry, Hofmann, Philip, Arman, Mohammad Alif, Urpelainen, Samuli, Lacovig, Paolo, Bignardi, Luca, Bluhm, Hendrik, Knudsen, Jan, Hammer, Bjørk, and Hornekaer, Liv

Abstract

Hydrogen functionalization of graphene by exposure to vibrationally excited H2molecules is investigated by combined scanning tunneling microscopy, high-resolution electron energy loss spectroscopy, X-ray photoelectron spectroscopy measurements, and density functional theory calculations. The measurements reveal that vibrationally excited H2molecules dissociatively adsorb on graphene on Ir(111) resulting in nanopatterned hydrogen functionalization structures. Calculations demonstrate that the presence of the Ir surface below the graphene lowers the H2dissociative adsorption barrier and allows for the adsorption reaction at energies well below the dissociation threshold of the H–H bond. The first reacting H2molecule must contain considerable vibrational energy to overcome the dissociative adsorption barrier. However, this initial adsorption further activates the surface resulting in reduced barriers for dissociative adsorption of subsequent H2molecules. This enables functionalization by H2molecules with lower vibrational energy, yielding an avalanche effect for the hydrogenation reaction. These results provide an example of a catalytically active graphene-coated surface and additionally set the stage for a re-interpretation of previous experimental work involving elevated H2background gas pressures in the presence of hot filaments.

Published
2018
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36. State-Resolved Reactivity of CH4(2ν3) on Pt(111) and Ni(111): Effects of Barrier Height and Transition State Location

Author

Bisson, Régis, Sacchi, Marco, Dang, Tung T., Yoder, Bruce, Maroni, Plinio, and Beck, Rainer D.

Abstract

Quantum state-resolved sticking coefficients on Pt(111) and Ni(111) surfaces have been measured for CH4 excited to the first overtone of the antisymmetric C-H stretch (2ν3) at well defined kinetic energies in the range of 10-90 kJ/mol. The ground state reactivity of CH4 is approximately 3 orders of magnitude lower on Ni(111) than on Pt(111) for kinetic energies in the range of 10-64 kJ/mol, reflecting a difference in barrier height of 28 ± 6 kJ/mol. 2ν3 excitation of CH4 increases its reactivity by more than four orders of magnitude on Ni(111), whereas on Pt(111) the reactivity increase is lower by two orders of magnitude. We discuss the observed differences in the state-resolved reactivity for the ground state and 2ν3 excited state of methane in terms of a difference in barrier height and transition state location for the dissociation reaction on the two metal surfaces.

37. Patterned formation of enolate functional groups on the graphene basal plane

Author

Régis Bisson, Valentin Calisti, Andrew Cassidy, Eric Salomon, Hendrik Bluhm, Thierry Angot, Stine S Pedersen, Liv Hornekær, Bisson, Régis, Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)

Subjects
Materials science, Oxygen atom role, Oxide, Graphene sheets, General Physics and Astronomy, 02 engineering and technology, Substrate (electronics), 010402 general chemistry, Photochemistry, 01 natural sciences, ATOMIC OXYGEN, law.invention, [PHYS.PHYS.PHYS-CHEM-PH] Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], chemistry.chemical_compound, X-ray photoelectron spectroscopy, law, Moiety, Physical and Theoretical Chemistry, THERMAL REDUCTION, IR(111), Graphene, Electron energy loss spectroscopy, OXIDE, Moiré, 021001 nanoscience & nanotechnology, 0104 chemical sciences, chemistry, Functional group, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Scanning tunneling microscope, 0210 nano-technology, Graphene Oxide
Abstract

International audience; Chemical functionalization of graphene is one method pursued to engineer new properties into a graphene sheet. Graphene oxide is the most commonly used chemical derivative of graphene. Here we present experimental evidence for the formation of enolate moieties when oxygen atoms are added to the graphene basal plane. The exotic functional groups are stabilized by simultaneous bond formation between the graphene sheet and the underlying Ir(111) substrate. Scanning tunneling microscopy images demonstrate the patterned nature of CO bond formation and x-ray photoelectron spectroscopy and high resolution electron energy loss spectroscopy are used to characterize the enolate moiety. The results present a new mechanism for the formation of patterned graphene oxide and provide evidence of a functional group rarely considered for graphene oxide materials. Graphene is a 2D semi-metal in which all carbon atoms are sp 2 hybridized. 1 Chemical functionalization of graphene is driven by the desire to engineer the physical and chemical properties of pristine graphene sheets, and to introduce new means of incorporating graphene interfaces with other materials. 2-4 The addition of simple atomic species, such as hydrogen, 5 oxygen 6,7 or fluorine, 8 has been shown to change the electronic band structure of graphene from that of a semi-metal to that of a semiconductor or insulator. Graphene oxide is a term used to describe graphene materials that have been subjected to oxidation reactions. Supported graphene oxide materials have been studied as sensor materials, for their potential magnetic properties and as clusters to form graphene oxide quantum dots. 9-12 The growth of metallic nanoparticles on supported graphene sheets is also facilitated by the presence of CO bonds at the graphene basal plane, 4 with attachment or cleavage of particle growth initiators dependent on the nature of the CO bond. 13 This may be a viable method for atomic layer deposition on graphene films, allowing for integration of graphene sheets in more complex electronic devices. 14 Consequently, the nature of the CO bond formed during synthesis of graphene oxide is of general interest and importance. It is widely assumed that an oxygen atom bonding to the basal plane of a graphene sheet is initially covalently bound through the formation of an epoxy group. 15-18 The stability of different oxygen moieties on metal-supported graphene sheets was, however, recently explored for graphene islands on Ru(0001). 19 Those authors, building on theoretical results from Jung et al., 20 provided the first experimental evidence for the existence of the enolate moiety when oxygen atoms bind to a graphene sheet supported by a metal substrate. Their calculations indicate that interaction with an underlying metallic substrate can guide the formation of enolate groups when an oxygen atom binds to one carbon atom, and the adjacent carbon atom is suitably positioned to bind down to an underlying metal atom. A 370 meV gain in energy was reported for the formation of an enolate group, versus an epoxy group, in certain areas of the moiré pattern formed between the graphene lattice and atoms from the Ru(0001) surface. 19 Graphene on Ru(0001), however, is already a strongly coupled system with good evidence for the preexistence of a carbon-metal bond even before oxygen atoms are introduced. 21 Hence, it is timely to consider the nature of the CO bond for other, less strongly coupled systems. Graphene on Ir(111) (Gr/Ir(111)) demonstrates weak van der Waals interaction between the graphene sheet and the Ir(111) surface atoms. 22 Moreover, single crystal graphene sheets with a low concentration of defects and highly oriented domains are routinely prepared on Ir(111) substrates following chemical vapour deposition. 23 The attachment of oxygen atoms to Gr/Ir(111) has been reported previously but the possibility of enolate formation was not considered. 15,16 Here, we revisit this system adding new high-resolution electron energy loss spectroscopy (HREELS) data to demonstrate that at a low flux of oxygen atoms, enolate formation dominates and occurs only at select sites on the Gr/Ir(111) surface, generating a long-range pattern of graphene oxide nano-dots. The slight lattice mis-match between the carbon atoms in the graphene sheet and the Ir(111) surface atoms leads to a long-range repeating moiré pattern. 23 The moiré unit cell contains: TOP regions where Ir surface atoms are positioned directly beneath the center of a hexagonal ring in the graphene sheet; and HCP and FCC regions, where every second C atom is positioned directly above an Ir atom. HCP and FCC regions differ in the arrangement of Ir atoms in the second and third Ir layer. The remaining carbon atoms, in between

Published
2018

38. Exciting H 2 Molecules for Graphene Functionalization.

Author

Kyhl L, Bisson R, Balog R, Groves MN, Kolsbjerg EL, Cassidy AM, Jørgensen JH, Halkjær S, Miwa JA, Grubišić Čabo A, Angot T, Hofmann P, Arman MA, Urpelainen S, Lacovig P, Bignardi L, Bluhm H, Knudsen J, Hammer B, and Hornekaer L

Abstract

Hydrogen functionalization of graphene by exposure to vibrationally excited H 2 molecules is investigated by combined scanning tunneling microscopy, high-resolution electron energy loss spectroscopy, X-ray photoelectron spectroscopy measurements, and density functional theory calculations. The measurements reveal that vibrationally excited H 2 molecules dissociatively adsorb on graphene on Ir(111) resulting in nanopatterned hydrogen functionalization structures. Calculations demonstrate that the presence of the Ir surface below the graphene lowers the H 2 dissociative adsorption barrier and allows for the adsorption reaction at energies well below the dissociation threshold of the H-H bond. The first reacting H 2 molecule must contain considerable vibrational energy to overcome the dissociative adsorption barrier. However, this initial adsorption further activates the surface resulting in reduced barriers for dissociative adsorption of subsequent H 2 molecules. This enables functionalization by H 2 molecules with lower vibrational energy, yielding an avalanche effect for the hydrogenation reaction. These results provide an example of a catalytically active graphene-coated surface and additionally set the stage for a re-interpretation of previous experimental work involving elevated H 2 background gas pressures in the presence of hot filaments.

Published
2018
Full Text
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39. The sticking probability of D2O-water on ice: isotope effects and the influence of vibrational excitation.

Author

Hundt PM, Bisson R, and Beck RD

Abstract

The present study measures the sticking probability of heavy water (D(2)O) on H(2)O- and on D(2)O-ice and probes the influence of selective OD-stretch excitation on D(2)O sticking on these ices. Molecular beam techniques are combined with infrared laser excitation to allow for precise control of incident angle, translational energy, and vibrational state of the incident molecules. For a translational energy of 69 kJ/mol and large incident angles (θ ≥ 45°), the sticking probability of D(2)O on H(2)O-ice was found to be 1% lower than on D(2)O-ice. OD-stretch excitation by IR laser pumping of the incident D(2)O molecules produces no detectable change of the D(2)O sticking probability (<10(-3)). The results are compared with other gas/surface systems for which the effect of vibrational excitation on trapping has been probed experimentally.

Published
2012
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40. State-resolved reactivity of CH4 on Pt(110)-(1 x 2): the role of surface orientation and impact site.

Author

Bisson R, Sacchi M, and Beck RD

Abstract

The reactivity of methane (CH(4)) on Pt(110)-(1 x 2) has been studied by quantum state-resolved surface reactivity measurements. Ground state reaction probabilities, S(0)(v=0) congruent with S(0)(laser-off), as well as state-resolved reaction probabilities S(0)(2nu(3)), for CH(4) excited to the first overtone of the antisymmetric C-H stretch (2nu(3)) have been measured at incident translational energies in the range of 4-64 kJ/mol. We observe S(0)(2nu(3)) to be up to three orders of magnitude higher than S(0)(v=0), demonstrating significant vibrational activation of CH(4) dissociation on Pt(110)-(1 x 2) by 2nu(3) excitation. Furthermore, we explored the azimuthal and polar incident angle dependence of S(0)(2nu(3)) and S(0)(v=0) for a fixed incident translational energy E(t)=32 kJ/mol. For incidence perpendicular to the missing row direction on Pt(110)-(1 x 2) and polar angles theta>40 degrees, shadowing effects prevent the incident CH(4) molecules from impinging into the trough sites. Comparison of this polar angle dependence with reactivity data for incidence parallel to the missing rows yields state-resolved site specific reactivity information consistent with a Pt(110)-(1 x 2) reactivity that is dominated by top layer Pt atoms located at the ridge sites. A comparison of S(0)(v=0) measured on Pt(110)-(1 x 2) and Pt(111) yields a lower average barrier for Pt(110)-(1 x 2) by 13.7+/-2.0 kJ/mol.

Published
2010
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